SACRAMENTO — Residents in coastal communities use far less water than their inland counterparts, but still find ways to cut back even more, residential per-capita water use figures released for the first time Tuesday show.

The State Water Resources Control Board is collecting per-capita data to better target conservation efforts as farms go fallow and reservoirs dry up. Gov. Jerry Brown called on Californians to reduce water use by 20 percent when he declared a drought emergency in January.

Californians are being asked to let their lawns go brown and take shorter showers as the likelihood of drought conditions worsening rises. The data released Tuesday shows big disparities in water habits.

Regional water use ranges from 84 gallons per-person, per-day in the San Francisco Bay Area to 252 in the Colorado River basin, which includes San Bernardino and Riverside. The figures exclude industrial, agricultural and business water users.

Median per-capita water use is 131 gallons, according to estimates from 351 suppliers serving roughly 33 million Californians. Residents in California’s three largest cities, Los Angeles, San Diego and San Jose, are using between 82 and 96 gallons a day.

In densely-packed San Francisco with lawns relatively rare, residents use 46 gallons a day. In the wealthy 5,000-person community of Cowan Heights in Orange County, water use is more than 569 gallons a day.

“If you have a place with a really high per capita (water use) and use is flat, it raises the question of what’s going on,” said Max Gomberg, senior environmental scientist with the water board.

Cowan Heights, for example, reported just a 2 percent drop in monthly water use in September compared to the year before. A request for comment was not immediately returned from a Cowan Heights spokesperson.

Regions with the lowest per-capita water use, however, are reporting some of the biggest drops in monthly water use. The San Francisco Bay Area region decreased water use by 15 percent despite already having the lowest per-capita consumption in the state.

Not all conservation is by choice. Residents in eastern Bay Area cities including Dublin, Livermore and Pleasanton have endured mandatory restrictions with severe cutbacks in water imports. Coastal Santa Cruz with limited and outdated storage is rationing water, with offenders paying steep fines and attending corrective classes.

Cities and local water agencies are required to report the figures under emergency regulations approved by the water board in July. Those regulations also included mandatory outdoor water restrictions backed up with the threat of up to $500 fines for violations.

Statewide monthly water use in September fell 10 percent compared to the same month in 2013, according to self-reporting by nearly 400 water agencies. But that’s down from an 11.5 percent decline reported for August.

Water officials say residents need to conserve more.

“Some rain and cooler weather are welcome relief, but they don’t mean the drought is over, not by a longshot,” said Felicia Marcus, chairwoman of the state water board, in a news release. “By far, conservation is still the most cost effective and common sense way to meet our water needs during this prolonged drought.”